Longitudinal waves have energy that vibrates parallel to the medium - a compression is the region of greatest density and the rarefaction the region of highest density .The rarefaction (much like the maximum amplitude in a transverse wave) has a region of lowest density, typically situated in the exact center of the region.
Answer: static electricity
Explanation:
When the plastic ruler is rubbed, friction opposes the motion and causes the transfer of electron from one surface to another such that plastic becomes negatively charged. When ruler is brought nearer to the paper, it induces the positive charge in the piece of paper.
Answer:
Change in momentum will be -4.4 kgm/sec
So option (A) is correct option
Explanation:
Mass of the ball is given m = 0.10 kg
Initial velocity of ball 
And velocity after rebound 
We have to find the change in momentum
So change in momentum is equal to 
( here negative sign shows only direction )
So option (A) will be correct answer
Well when you eat you get energy and then you use it to ride up the hill sorry I don't know how it is classified
